Best Load Testing Tools in 2026
Three of these are free to run on your own machines. The hosted ones bill virtual users, test hours or reports, and those units are not interchangeable.
k6 is free as open source. Grafana Cloud k6 is $19 a month with 500 virtual-user hours included, then $0.15 per VUh. JMeter and Locust are free to run yourself. Gatling Community is free; Enterprise Basic is €89 a month billed annually. Artillery Cloud is free for 30 reports a month, then $199 on Team.
Key facts5 tools compared: k6, Apache JMeter, Gatling, Locust, Artillery
- 5 tools compared: k6, Apache JMeter, Gatling, Locust, Artillery
- Apache JMeter (best for: Teams that already have JMeter scripts, or that need protocols beyond HTTP without a vendor): Free (Apache License 2.0); you pay for the machines
- Gatling (best for: Teams that want hosted Gatling with a published limit on hours and generators): From €89/mo (Enterprise Basic, billed yearly); Community free
- Locust (best for: Python teams that want scenarios as code and will run their own workers): Free, open source; you pay for the worker machines
Load testing tools all generate traffic. They do not all sell the same unit of traffic. k6 Cloud bills virtual-user hours. Gatling Enterprise bills test hours on a load generator. Artillery Cloud bills reports. JMeter and Locust bill nothing, because you bring the machines.
A comparison that lines up their headline prices is therefore meaningless. $19, €89 and $199 buy different things, and the free tools are free until you count the box that runs them.
Top Picks
Based on features, real-world fit, and value for money.
The JavaScript load tester: free on your machines, $19 a month plus $0.15 per virtual-user hour when Grafana runs it.
From $19/mo + $0.15 per virtual-user hour (Grafana Cloud k6 Pro); open source and cloud Free
Teams that want tests as JavaScript in Git, and a hosted runner when the laptop is not enough
Free (Apache License 2.0); you pay for the machines
Teams that already have JMeter scripts, or that need protocols beyond HTTP without a vendor
Scala-or-Java tests, free locally, €89 a month when you want their generators for one hour.
From €89/mo (Enterprise Basic, billed yearly); Community free
Teams that want hosted Gatling with a published limit on hours and generators
| Tool | Pricing | Best for |
|---|---|---|
| k6 | From $19/mo + $0.15 per virtual-user hour (Grafana Cloud k6 Pro); open source and cloud Free | Teams that want tests as JavaScript in Git, and a hosted runner when the laptop is not enough |
| Apache JMeter | Free (Apache License 2.0); you pay for the machines | Teams that already have JMeter scripts, or that need protocols beyond HTTP without a vendor |
| Gatling | From €89/mo (Enterprise Basic, billed yearly); Community free | Teams that want hosted Gatling with a published limit on hours and generators |
| Locust | Free, open source; you pay for the worker machines | Python teams that want scenarios as code and will run their own workers |
| Artillery | From $199/mo (Team); Cloud Free ($0); annual saves 20% | Teams that run a limited number of YAML or JavaScript suites each month and want hosted reports |
Pricing read from each vendor's own pricing page, checked Aug 2026. Every vendor here publishes a price.
k6
The JavaScript load tester: free on your machines, $19 a month plus $0.15 per virtual-user hour when Grafana runs it.
- Pricing
- From $19/mo + $0.15 per virtual-user hour (Grafana Cloud k6 Pro); open source and cloud Free
Best for: Teams that want tests as JavaScript in Git, and a hosted runner when the laptop is not enough
Pros
- The OSS runner is complete, so you can keep tests in CI without paying
- VUh pricing is published, including the formula: (max VUs × minutes) / 60
- 500 VUh a month is enough for regular API checks before you hit overage
Cons
- Browser tests multiply the VUh cost, and a quote that assumed protocol VUs will be wrong
- The $19 platform fee is a floor even in a quiet month
Apache JMeter
The old standard: a GUI, a huge plugin list, and a price of zero.
- Pricing
- Free (Apache License 2.0); you pay for the machines
Best for: Teams that already have JMeter scripts, or that need protocols beyond HTTP without a vendor
Pros
- Genuinely free, with no hosted upsell required to run a test
- Protocol coverage and plugins still beat most newer tools
- Twenty years of Stack Overflow answers for the ugly parts
Cons
- The GUI produces plans that are painful to review in Git
- Distributed mode is yours to operate, including the generators
Gatling
Scala-or-Java tests, free locally, €89 a month when you want their generators for one hour.
- Pricing
- From €89/mo (Enterprise Basic, billed yearly); Community free
Best for: Teams that want hosted Gatling with a published limit on hours and generators
Pros
- Community Edition is free and is the same scripting model as Enterprise
- Basic publishes a hard cap: 1 hour, 1 generator, 2 seats, so the bill is predictable
- The recorder and the as-code SDK cover both first-pass and CI
Cons
- €89 for 60 minutes is expensive if you run tests daily rather than before a launch
- Prices are in euros
Locust
Write users in Python, run as many workers as you have boxes, pay nothing to the project.
- Pricing
- Free, open source; you pay for the worker machines
Best for: Python teams that want scenarios as code and will run their own workers
Pros
- Tests are ordinary Python, so the same people who write the service can write the load
- Distributed workers are a first-class idea, not a paid add-on
- No vendor meter, so a long soak test costs only electricity
Cons
- There is no official hosted dashboard in the open-source project
- You own scaling, result storage and access control
Artillery
A Node load tester whose cloud bill is reports, not virtual users.
- Pricing
- From $199/mo (Team); Cloud Free ($0); annual saves 20%
Best for: Teams that run a limited number of YAML or JavaScript suites each month and want hosted reports
Pros
- Free includes the CLI and 30 reports, which is enough to prove the workflow
- The Team cap of 1,000 reports is a lot if a report is a CI run, not a 4-hour soak
- Load testing and E2E sit in one subscription
Cons
- A report-based meter punishes chatty CI more than a short heavy test
- $199 is a jump from $0, with no published step between them
What it is
A load testing tool drives concurrent virtual users against an HTTP API, a website or a protocol, then reports latency, errors and saturation. The script lives in code (JavaScript, Java, Python, Scala) or in a recorder. The runners live either on your CI agents or on a vendor's generators.
The category split is simple. Open-source runners are free and local. Hosted platforms rent you generators, dashboards and a place to keep results. Most vendors now sell both: a free engine, and a cloud that meters the run.
Why it matters
The bill is set by how you count a test, not by how good the charts look. A 10-minute test at 100 virtual users is 16.67 VUh on Grafana Cloud k6. The same shape on Gatling Basic consumes part of a 1-hour, 1-generator allowance. On Artillery Free it consumes one of 30 monthly reports. Those are not comparable line items.
The other cost is engineering time writing the script twice. Teams that pick a hosted recorder and later need the test in CI discover they have been using a product, not a file they can commit.
Key features to look for
Pricing
k6, Gatling and Artillery publish list prices, checked 26 August 2026. JMeter, Locust, k6 open source and Gatling Community are free on your own machines, Artillery Cloud Free is $0, and Gatling Enterprise is quote-only (on request).
The cheapest paid entry is Grafana Cloud k6 Pro at $19 a month, with 500 virtual-user hours included and $0.15 per virtual-user hour after that.
Costs jump from Artillery's free plan to Team at $199 a month, then Business at $499 a month and Enterprise add-ons from $1,199 a month. Gatling Basic at €89 a month billed annually jumps to Team at €356 a month billed annually. Hosted prices buy different units (virtual-user hours, minutes on a generator, or reports), and Artillery annual billing saves 20%.
| Plan | Price | Best for |
|---|---|---|
| k6 open source | Free | Full runner on your own machines |
| Grafana Cloud k6 Free | Free | 500 virtual-user hours per month |
| Grafana Cloud k6 Pro | $19/mo, then $0.15/VUh | 500 VUh/mo included; automatic volume discounts; higher price for browser than protocol |
| Apache JMeter | Free | Apache License 2.0; you pay for the machines |
| Gatling Community | Free | Free for local use |
| Gatling Enterprise Basic | €89/mo billed yearly (€1,068/yr) or €99/mo | 60 minutes, 1 load generator, 2 seats, 60,000 VUs cap |
| Gatling Team | €356/mo billed yearly (€4,272/yr) or €396/mo | 300 minutes, 3 generators, 10 seats |
| Gatling credit | 1 credit = 1 minute on 1 generator | Billing unit for the minute-based plans |
| Gatling Enterprise | Custom quote | Enterprise plan, price on request |
| Locust | Free | Open source; you pay for the worker machines |
| Artillery Cloud Free | $0 | 30 reports/month, 1-month retention, 2 members, 5 workers/test, 30-minute tests, CLI usable |
| Artillery Team | $199/mo; annual saves 20% | 1,000 reports, 6-month retention, 8 members, 25 workers, 2-hour tests |
| Artillery Business | $499/mo; annual saves 20% | 2,500 reports, 18-month retention, unlimited members and workers |
| Artillery Enterprise | From $1,199/mo; annual saves 20% | Enterprise add-ons |
The bottom line
For most teams the runner should be free. k6 if the team writes JavaScript, Locust if they write Python, JMeter if the scripts already exist or you need odd protocols. Pay for generators when a laptop cannot produce the load, not before.
When you do pay, pick the unit that matches how you test. Regular API checks: Grafana Cloud k6 at $19 plus $0.15/VUh. Occasional launch tests with a published hour cap: Gatling Basic at €89. Many CI reports and a hosted archive: Artillery Team at $199. Do not buy all three.
Frequently asked questions
What is the best free load testing tool?
How much does Grafana Cloud k6 cost?
Is JMeter still worth using in 2026?
k6 vs Gatling vs Artillery: which should I pay for?
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